1. Field of Invention
The present invention relates to a fan and a manufacturing method thereof, and in particular, to a thin fan and a manufacturing method thereof.
2. Related Art
With the rapid progress of electronic industry, the electronic devices, such as chips, in the electronic product generate more and more heat after operation. In order to dissipate the heat generated from the electronic devices, a heat sink with a fan thereon is usually equipped to the surface of the heat-generating electronic device. The cold airflow generated by the fan can acts enforced heat dissipation to the heat sink, and dissipates the waste heat generated from the heat-generating electronic devices.
FIG. 1A is a schematic diagram of a conventional fan, and FIG. 1B is a sectional diagram of the fan shown in FIG. 1A. For the convenience of a view and description, the upper casing of the housing is omitted in FIGS. 1A and 1B. As shown in FIGS. 1A and 1B, the fan 1 includes an impeller 11, a stator 12, a circuit board 13, a housing 14, a bearing 15, and a rotor 16. The bearing 15 connects the impeller 11 and the housing 14, and the housing 14 covers the impeller 11. The stator 12 and the circuit board 13 are disposed in the housing 14, and disposed opposite to each other. The control circuit of the circuit board 13 can raise the voltage and current of the motor to make the motor magnetic excitation, and then the magnetic polarity of the motor can be converted alternately by the chip control, so that the mutual attraction and repulsion are generated between the motor and the magnet, which driving the rotor 16 and the impeller 11 to rotate.
In the current manufacturing process of the fan, a circuit board with some surface mounted devices thereon is assembled with a stator and a bearing to form an assembly, and then the assembly is equipped with the rotor and the impeller into the housing to accomplish the fabrication of the fan.
With more and more compactly designed electronic products, the fans for heat dissipation also need to be designed compactly. Nevertheless, the height and the space need to be reserved in the fan to accommodate the circuit board and the electronic devices disposed thereon, so the fan is hard to be compacted in height and size effectively. Besides, because the design of the shape and area of the circuit board is restricted by the airflow outlet channel and mechanism, the miniaturization of the fan is further limited.
Therefore, it is an important subject to provide a thin fan that can be reduced in height and maintain the heat-dissipating effect by more effectively using the limited height space.